1. Field
The field of the invention is apparatus and methods for preparation of the cysts of the brine shrimp (Artemia spp.) to be containerized for storage, shipment and later hatching into nauplii for use as fish food.
2. State of the Art
Developing brine shrimp are in nature contained within protective spherical cysts. The cysts are found floating in the dense concentrated brine, for example, of the Great Salt Lake, Utah, and are harvested by seining and bagging. As originally harvested, the bagged cysts are accompanied by various lake and shore detritus and flotsam, as well as water and salt, and must be washed and seived with fresh water to remove the salt and debris. Since whole, viable cysts will not float in fresh water, as will broken dead cysts, settling and skimming may be employed to dispose of the latter. The water is then drained off through a fine mesh seive which retains the viable cysts. The cysts may then be bagged and further dewatered in a centrifugal spin tank.
After dewatering, the cysts must be further dried before being placed in sealed cans for storage and shipment. Heretofore, the damp mass of cysts has been spread in thin layers in trays and allowed to dry. Both atmospheric and oven drying environments have been utilized. Periodic manual stirring of the mass of cysts is sometimes used. With these procedures, individual cysts become caked together into a crumbly aggregate. However, the cysts must somehow later be separated before hatching, or the cake at least crumbled to reasonably small clumps of aggregated cysts. This breaks and destroys substantial numbers of the cysts. There is therefore a definite need for a method of brine shrimp cyst preparation for canning which is more efficient in terms of surviving cysts.